Systems and methods may be provided embodying a novel approach to measuring degradation (or distortion) by analyzing disparity maps from original 3D video and reconstructed 3D video. The disparity maps may be derived using a stereo-matching algorithm exploiting 2-view stereo image disparity. An overall distortion measure may also be determined resulting from the weighted sum of plural measures of distortions, one of the plural distortion measures corresponding to a measure of disparity degradation, and another one corresponding to a measure of geometrical distortion. The measure (or overall distortion measure) is used during real-time encoding to effect various decisions, including mode decision in the coding of each corresponding stereo pair, and in rate control (including stereo pair quantization).